Haha – Many of your sentiments really resonate with me. As an engineer by day, I very much appreciate the fact that there are many solutions to any given problem and when reviewing advice – I think of it a similar way. Whether it is the nuances of drag/lines/flies or something else, I still try to reinforce why something works if I think it does (or at least come up with a believable reason) --then constantly see if future observations support that. It represents a lot of the fun in this pursuit for me.
I do fish futsu’s – I fished them a lot when I started trying to wean myself off heavy nymphs or beadhead wet fly variations. The idea of anchoring in the water/the current, especially with light tippet really helped me to understand the contact and drag game…not always in tight contact, but being able to gently tug a little and determine when you’ve regained it.
I was out this morning on a tiny creek and I’ve been fishing a simple hybrid fly that is a “jun in the back, futsu up top” – I like this because it both can anchor/push water and it also has some wiggle without having to move it a lot. I don’t know that the pattern really makes much difference, but my manipulations are usually attempting at mimicking what I’ve seen craneflies and caddis do on fast water.
I need to do a lot more screwing around because there are times when I’m sure that a futsu style fly would win the day but a jun tends to win.
I tend to agree that absolutes are not helpful. I have line in/on the water all the time if I think it makes sense. It is always some compromise, and my laziness often funnels the results of a lot of experimentation down into ways do keep the same rig for almost all situations.